The present invention provides methods and compositions for modulating the expression of Akt3, and antisense and ribozyme compounds specifically hybridizable with Akt3.
Akt3 is one of three serine/threonine protein kinases implicated in mediating apoptosis, stimulating cell growth, and regulating other biological responses. Akt1 and Akt2 are also within this group. (Coffer, P. J. et al., Biochem. J. 335:1-13, 1998.) Studies have suggested a role of Akt1 and Akt2 in cancer. For example, gene amplification resulted in increased Akt2 protein and mRNA in several cancers. (Staal, S. P. et al., P.N.A.S. 84:5034-5037, 1987; Cheng, J. Q. et al., P.N.A.S. 93:3636-3641, 1996; Cheng, J. et al., P.N.A.S. 89:9267-9271.)
Due to its potential role in cancer, there is a need in the art for compositions and methods that regulate expression and/or function of each Akt protein, including Akt3.
The present invention provides, in one embodiment, inhibitors of Akt3. Inventive inhibitors include, but are not limited to, antisense molecules, ribozymes, antibodies or antibody fragments, proteins or polypeptides as well as small molecules. Exemplary antisense molecules comprise at least 10, 15 or 20 consecutive nucleotides of or hybridize under stringent conditions to the nucleic acid of SEQ ID NO:1. More preferred are antisense molecules that comprise at least 25 consecutive nucleotides of or hybridize under stringent conditions to the sequence of SEQ ID NO:1. Representative antisense molecules are provided herein as SEQ ID NOS:2-6 and 12-19.
In further embodiments, compositions are provided that comprise one or more Akt3 inhibitor in a pharmaceutically acceptable carrier.
Additional embodiments provide methods of decreasing Akt3 gene expression or biological activity.
The invention provides an antisense oligonucleotide comprising at least one modified internucleoside linkage.
The invention further provides an antisense oligonucleotide having a phosphorothioate linkage.
The invention still further provides an antisense oligonucleotide comprising at least one modified sugar moiety.
The invention also provides an antisense oligonucleotide comprising at least one modified sugar moiety which is a 2xe2x80x2-O-methoxyethyl sugar moiety.
The invention further provides an antisense oligonucleotide comprising at least one modified nucleobase.
The invention still further provides an antisense oligonucleotide having a modified nucleobase wherein the modified nucleobase is 5-methylcytosine.
The invention also provides an antisense compound wherein the antisense compound is a chimeric oligonucleotide.
The invention provides a method of inhibiting the expression of human Akt3 in human cells or tissues comprising contacting the cells or tissues in vivo with an antisense compound or a ribozyme of 8 to 35 nucleotides in length targeted to a nucleic acid molecule encoding human Akt3 so that expression of human Akt3 is inhibited.
The invention further provides a method of modulating growth of cancer cells comprising contacting the cancer cells in vivo with an antisense compound or ribozyme of 8 to 35 nucleotides in length targeted to a nucleic acid molecule encoding human Akt3 so that expression of human Akt3 is inhibited.
The invention still further provides for identifying target regions of Akt3 polynucleotides. The invention also provides labeled probes for identifying Akt3 polynucleotides by in situ hybridization.
The invention provides for the use of an Akt3 inhibitor according to the invention to prepare a medicament for modulating cell proliferation.
The invention also provides a pharmaceutical composition for inhibiting expression of the Akt3, comprising an antisense oligonucleotide according to the invention in admixture with a physiologically acceptable carrier or diluent.
The invention further provides a ribozyme capable of specifically cleaving Akt3 RNA, and a pharmaceutical composition comprising the ribozyme.
The invention also provides small molecule inhibitors of Akt3 wherein the inhibitors are capable of reducing the activity of Akt3 or of reducing or preventing the expression of Akt3 mRNA.